Endocrine Abstracts

Autoimmune hypothalamitis has been implicated in idiopathic central diabetes insipidus (DI) due to antibodies against vasopressin producing hypothalamic cells. Lymphocytic infiltration of hypothalamus has been reported in patients with lymphocytic hypophysitis (LH) manifesting as hypopituitarism with DI. These patients can also have other associated autoimmune diseases. Here, we report a case of a male patient who presented with headache, poor orientation, partial hypopituitarism, diabetes insipidus, and whose MRI findings revealed involvement of hypothalamus, posterior pituitary and infundibulum. 40 years old male patient was admitted to the hospital with symptoms of polyuria (8–10 lt/day), polydipsia, headache. Urine density was low (1005). Hormonal testing revealed low IGF1, testosterone, normal cortisole levels, but thyroid hormone levels were in the normal range with high TSH and anti-TPO levels. Response to LHRH and ACTH stimulation tests were normal. Sellar fossa and pituitary gland size, pituitary gland enhancement were normal at MRI. Increased T2 signal intensity in the optic chiasm, hypothalamus, infundibulum and contrast enhancement in the T1-contrasted series were noted. This finding is most visible in 2016, but regressed in 2017. As the lesion did not cause any visual symptoms and did not have features typical of tumors of the suprasellar area, and the patient did not give consent for a pituitary biopsy, a strict follow-up and see policy was chosen. Polyuria improved after oral administration of desmopressin 2×120 μg. We did not give steroid treatment, levothyroxin was administered for the subclinical hypothyroidism. The symptoms improved in six months without steroid treatment, anterior pituitary functions returned to normal. The lesion spared the anterior pituitary. Hence, it is speculated that anterior pituitary dysfunction could be consequent to either deficiency of hypothalamic releasing hormones due to the involvement of hypothalamic nuclei or microscopic involvement of anterior pituitary. He is still being followed with desmopressin and levothyroxin. As far as we know this is the first case of hypothalamitis and infundibulo-neurohypophysitis presenting with symptoms of DI and partial hypopituitarism. To conclude, in a patient presenting with headache, hypopituitarism and a suprasellar mass, hypothalamitis also should be considered in differential diagnosis. Because it is a self-limiting condition, close follow-up with clinical and laboratory testing can be sufficient for most of the patients. But also according to the literature, these patients may benefit from course of steroid and immunosuppressive drugs